Question

If the velocity ratio for an open belt drive is 8 and the speed of driving pulley is 800 r.p.m, then considering an elastic creep of 2% the speed of the driven pulley is

(a) 104.04 r.p.m

(b) 102.04 r.p.m

(c) 100.04 r.p.m

(d) 98.04 r.p.m

I had been asked this question at a job interview.

The doubt is from Pulleys topic in chapter Belt, Rope and Chain Drives of Machine Kinematics

Answer 1

The correct choice is (d) 98.04 r.p.m

To explain I would say: Velocity Ratio = Velocity of belt on driver/Velocity of belt on driven

Velocity of belt on driven = 800/8 = 100 r.p.m

Elastic creep = velocity of belt at driven pulley – Velocity of driven pulley

0.02 × Vp = [100-Vp]

Vp = 100/1.02 = 98.04r.p.m.